The amendment, introduced by Rep. Paul Broun (R-Ga.), says “the Department of Defense may not use a drone to kill a citizen of the United States,” but that protection “shall not apply to an individual who is actively engaged in combat against the United States.”

The distinction likely wouldn’t change much, as the legal standard for killing American civilians, according to Ilya Somin, a law professor at George Mason University School of Law, is that the person targeted must be a “combatant in a relevant war.”

The U.S. government has killed at least four Americans with drone strikes overseas, most notably Anwar al-Awlaki, who died in Yemen in September 2011. The Obama administration said that al-Awlaki was a “continuing and imminent threat.”

According to Broun, the amendment was introduced to help “protect U.S. citizens from government overreach.”

Broun and several other lawmakers, most notably Rand Paul, have raised concerns that the government will one day use a drone to kill an American on U.S. soil.

The 2014 National Defense Authorization Act, H.R. 1960, passed Friday by a 315-108 vote. The Senate Armed Forces Committee completed its markup of the bill Friday and will be considered shortly.

In a May speech, Barack Obama finally addressed America’s targeted killing program. At the time, he said that he “[does] not believe it would be constitutional for the government to target and kill any U.S. citizen – with a drone, or a shotgun – without due process. Nor should any president deploy armed drones over U.S. soil.”

“But when a U.S. citizen goes abroad to wage war against America – and is actively plotting to kill U.S. citizens; and when neither the United States, nor our partners are in a position to capture him before he carries out a plot – his citizenship should no more serve as a shield than a sniper shooting down on an innocent crowd should be protected from a SWAT team,” Obama added.

Obama said that al-Awlaki was “continuously trying to kill people” and that his administration briefed both the Department of Justice and Congress before the strike was taken.

Broun and many others are concerned about the way the administration has been using the 2001 Authorization to Use Military Force. The Senate is now working on its own version of the bill.